Methods, systems, and devices for techniques for forming memory structures are described. Forming a memory structure may include etching a stack of material including a conductive line, a first electrode and a sacrificial material to divide the stack of material into multiple sections. The process may further include depositing an oxide material in each of the first quantity of channels to form multiple oxide materials. The sacrificial material may be etched to form a second channel between two oxide materials of the multiple oxide materials. Memory material may be deposited over the two oxide materials and the second channel, which may create a void in the second channel between the memory material and the first electrode. The memory material may be heated to fill the void in the second channel.